الفهرس 
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Abstract
Mosquitoes were surveyed in eight selected areas in Qalyubiya Governorate including agricultural, semi-desert and desert areas namely; Kafr Saad, Atreeb, Shiblanga, Batmda, Kafr Tahla, Tant El-Jazera, Kafr Tahoria and Akrasha. Water collections which may provide breeding habitats for mosquitoes in Qalyubiya Governorate were surveyed throughout the period from April 2009 to March 2011. Mosquito larvae were collected on monthly basis from 14 different breeding places in eight areas. A total of 1800 from 2821 sites (63.8%) were found positive for mosquitoes, including 312 canals, 271 pools, 191 unused wells, 166 rice fields, 142 irrigation channels, 130 ponds, 128 drainages, 115 catch basins, 85 irrigation basins, 82 ditches, 70 swamps, 66 temporary pools, 22 unused tires and 20 irrigation drainage tubes. Mosquito larvae were found in a variety of water collections including temporary, permanent, natural or man-made habitats. Permanent and semi-permanent water collections were the main sites for mosquito breeding. Nine mosquito species were identified in the study area namely, Culex pipiens 64.7%, Culiseta longiareolata 13.5%, Cx. antennatus 8.8%, Aedes caspius 6.3%, Cx. vagans 2.5%, Cx. decens 1.9%, Cx. perexiguus 0.9%, Cx. univittatus 0.8% and Anopheles multicolor 0.6%. Culex vagans, Cx. decens and Anopheles multicolor were not recorded before in Qalyubiya Governorate. The impact of physicochemical parameters (temperature, pH, Ammonia, Nitrate, salinity and dissolved oxygen) on the mosquito larvae density was determined. Simple and Multiple regression models showed that temperature, Ammonia and Nitrate were the best predictors for mosquito larval density (P = 0.0397), (P = 0.0241) and (P = 0.0040), respectively. The year-round presence of immature mosquitoes indicates that climatic conditions of the area are not limiting to the development of most prevailing mosquito species. The obtained results showed that greater numbers of mosquito larvae were collected from catch basins (187.5 larvae/dip) followed by unused wells (145.0), drainages (136.4), ponds (118.9), irrigation channels (105.1), pools (103.4), irrigation basins (81.7), canals (77.7), ditches (58.5), swamps (54.1), temporary pools (37.0), rice fields (19.1), unused tires (8.5) and irrigation drainage tubes (5.0) in eight areas. The presence of mosquito larvae in these breeding places indicated that they are strongly attractive to adult females. Duncan’s multiple range test for variables between type of the breeding sites and density of mosquito larvae showed that there was a significant variation between the density of mosquito larvae and type of the breeding site (df= 13, F= 149.26, P= 0.0001). Also, our results revealed that unused wells were found to be the most important breeding habitat in Kafr Tahoria, Shiblanga, Batmda and Kafr Tahla areas. Pools were found to be the most important breeding habitat in Kafr Saad and Tant El-Jazera areas. While, catch basins and drainages were found to be the most important breeding habitats in Atreeb and Akrasha areas, respectively. Catch basins, unused wells, pools and drainages are playing the major role in mosquito problem in Qalyubiya Governorate. Mosquito larvae were abundant throughout the two years of study period. Mosquito larvae have one peak of abundance in September for both years of investigation, where the densities were 738.4 larvae/dip in 2009 and 768.0 larvae/dip in 2010, when the average temperature recorded was 29.8 °C. The highest abundance of larvae was recorded in summer months from June to October 2009 (677.5, 690.9, 696.4, 738.4, 659.4 larvae/dip, respectively and from June to October 2010 (703.5, 673.9, 721.8, 768.0, 710.5 larvae/dip respectively). The lowest abundance of larvae was recorded in January, February and March of both years (2009-2010) when the average temperature recorded was 13.8 °C. Simple regression analysis revealed a close and direct relation between temperature and larval abundance.
Some experiments were conducted in the laboratory and field to study the efficiency of some non-conventional control agents and the extent of their impact in control programs. In the laboratory, Mosquito fish Gambusia affinis was the most efficient predator against mosquito larvae, where the average number of larvae consumed by female and male mosquito fish Gambusia affinis was 125.7±1.8 and 84.7±1.1, respectively. In field, we applied Gambusia affinis fishes in two sites; a pool and an unused well, The results showed that Gambusia affinis was more efficient mosquito predator in the pool than in the unused well regarding consumption and long persistence, where the percent reduction in culicine larvae reached 98.8% and 52.8% at 24 days post-treatment and 92.1% and 51.4 at 18 days post-treatment in pupae during winter season, respectively. In summer season, the percent reduction in culicine larvae reached 96.9% and 40.6% at 15 days post-treatment and 88.3% and 33.8% at 18 days post-treatment in pupae, respectively. Fishes introduced into pools were efficient for 45 and 30 days, whereas those introduced into unused wells were efficient for 21 and 12 days during winter and summer seasons, respectively. Mosquito dunks® Bti was more effective and had long persistence in clean pool than polluted pool, where mosquito dunks Bti caused 99.7% and 83.6% larval reduction at 9 days post-treatment, also 96.1% and 88.6% at 12 days post-treatment, respectively in winter season. While, in summer season larval reduction reached 93.2% and 70.1% at 12 days post-treatment, respectively with persistence for 30 days in winter and 18 days in summer. Altosid XR briquettes had long-lasting effect on mosquito population during winter than summer seasons, where inhibition emergence of adult reached 96% and 94% for 35 and 15 days post-treatment, respectively. Monomolecular surface film, Aquatain had long-lasting effect on mosquito population at a dose of 2 ml/m2 than 1 ml/m2, where it caused 100% reduction after 2 and 4 days post-treatment in winter with stability 19-13 days, respectively, while in summer it reached 92% and 84.2% reduction for 3 days post-treatment with stability 9-7 days, respectively. The effect of treated-curtains with 10 ml/m2 lambdacyhalothrin on inhibited mosquito adults’ entry was determined by using cotton and polyester curtains. We noted that cotton-treated curtains were suitable than polyester curtains in reduction adult’s mosquito inside house than polyester-treated curtains with stability for 10 and 4 days post-treatment, respectively. The efficiency, persistence and cost of different control agents were included.